A filament drive apparatus (101, 401) for use in an additive manufacturing system comprises a frame (102, 402) that supports a drive mechanism (103, 403). The drive mechanism (103, 403) comprises a roller arrangement (104, 404) and a belt drive arrangement (105, 405). The roller arrangement (104, 404) comprises at least one roller (106, 406) and presents a first filament engaging surface (107, 407). The belt drive arrangement (105, 405) comprises a belt (108, 408) that presents a second filament engaging surface (109, 409). The second filament engagement surface (109, 409) faces the first filament engaging surface (107, 407). An elongate and arcuate pathway (P) is defined between the first filament engaging surface (107, 407) and the second filament engaging surface (109, 409) along which advancement of a filament (110) in a drive direction is guided under the operation of the drive mechanism (103, 403).